An operation unit has an operation surface for accepting an input operation. In a plan view, the operation surface has a rectangular contour including a plurality of sides and a plurality of corner portions. When each point at which extensions of adjacent two of the plural sides cross each other is defined as a virtual intersection, and when an intersection at which respective diagonals linking the virtual intersections cross each other is defined as a virtual center, the contour of the corner portion crosses the diagonal that passes through the virtual intersection and the virtual center, at a point between the virtual intersection in the vicinity of the corner portion and the virtual center. The corner portions is a specific corner portion having an intersection with the diagonal at a position closer to the virtual center than the adjacent two corner portions.